In an amusing guest appearance as herself on “Will & Grace,” Patti LuPone is dissed by a hysterically irate Jack McFarland, the character played by Sean Hayes. “People either love me, or they hate me,” she comments with the proud forbearance of one accustomed to both extremes.

There’s no question that Ben Rimalower’s position on that divisive diva puts him squarely in the adoration camp, even when La LuPone is threatening legal action against him. But “Patti Issues,” his solo show playing in the upstairs cabaret space at the Duplex, is far more entertaining than any ordinary young gay man’s account of his obsession with a Broadway legend. Which is not to say it isn’t also show-queen heaven.

This is not a coming-out memoir. Despite having been put through therapy three times before the age of 11, Mr. Rimalower appears to have traveled a relatively uncomplicated path to acceptance of his homosexuality, even before he could put a name to it.

“Patti Issues” is more about the baggage of having a self-dramatizing gay dad who burned down the closet door, bailed on the family for a string of boyfriends and left Ben and his sister with their angry mom. Patti LuPone was Mr. Rimalower’s escape valve, and her “fierceness” his empowering inspiration.

Directed by Aaron Mark, the show is a tight hourlong monologue that pairs a well-honed script with an engagingly spontaneous delivery and a nose for sharp, observational comedy.

Mr. Rimalower traces the evolution of his LuPonophilia from his awed introduction to the original Broadway cast double album of “Evita.” (The San Fernando Valley record store where he had a gift certificate didn’t stock the earlier British recording.)

Fandom blossomed into acquaintanceship and professional association via a connection to the director Lonny Price, whom Mr. Rimalower assisted on the New York Philharmonic’s 2000 gala presentation of “Sweeney Todd,” starring Ms. LuPone as Mrs. Lovett.

Mr. Rimalower was asked to run lines with the star in her apartment after rehearsal one evening. His giddy recollection of finding himself on a love seat next to Ms. LuPone as she bellowed “The Worst Pies in London” is so ecstatically vivid, and his rendering of her so affectionately on target, that you half expect her to emerge from the wings with a tray of malodorous pastries.

An assignment to transfer Ms. LuPone’s personal archive of performance footage to DVD gave Mr. Rimalower access to “the Holy Grail of Patti video,” her celebrated late-night 1980 cabaret show at the Chelsea club Les Mouches, now defunct.

Mr. Rimalower directed the musical theater performer Leslie Kritzer in a critically lauded re-creation of that act at Joe’s Pub in 2006. This was done initially with Ms. LuPone’s blessing. (“Sounds like a blast. Break a leg, Doll.”) Then, when a recording was broached, not so much.

If there’s a slight weakness to “Patti Issues,” it’s that Mr. Rimalower’s dad disappears from the picture for a long stretch, just as he did in real life. And the awkward reunion of father and son when they find themselves seated a row apart to see Ms. LuPone in “Gypsy” seems somewhat anticlimactic.

But closure really happens only in fiction, so perhaps the show’s abrupt, unresolved ending is fitting. As a gay man’s coming-of-age story wrapped up in more than 20 years of undiminished idol worship, Mr. Rimalower’s funny, tender reminiscence rides an infectious rainbow high.

Correction:Jan. 3, 2013

An earlier version of this article misstated the name of the director of the show “Patti Issues.” He is Aaron Mark, not Aaron Monk.